The latest developments in engineering, as part of Progressive Engineer (www.ProgressiveEngineer.com), the online magazine and information source with a sustainability slant.

Sunday, November 6, 2016

Lancaster County wastewater authority honored for using recycled glass

The Pennsylvania Recycling Markets Center (PRMC) recently honored the Northern Lancaster County Authority (NLCA) of Denver, PA with the 2016 William M. Heenan, Jr. Recycling Markets Development Award for its commitment to creation of new markets for recycled color-mixed glass. PRMC recognized the use of recycled glass as a growing medium for the reed bed filtration system at the Authority's Beam Road Wastewater Treatment Plant. To RMC's knowledge, the plant is the first location to use sharp-free, manufactured recycled glass aggregate for this purpose in the United States.

A reed bed or constructed wetland is essentially a type of water filtration system that mirrors the way natural wetlands break down waste in water and filter impurities. Wetland reeds, specifically Phragmites austalis, are cultivated in a recycled glass aggregate filter bed where the plant roots and natural microbial processes turn wastewater solids into treated water and benign solids. Free of chemicals and odors, these beds have proven cost-effective and energy-efficient, and they significantly reduce or even eliminate the need for disposal of the solids. Reed bed systems have been shown to reduce the volume of solids by as much as 90 percent.

"Typically, the growing media for reed bed wastewater filtration is a very porous, fine aggregate such as sand," explains Jason Coyle, plant superintendent for NLCA. "Our sand was 20 years old and had broken down over time. As a planting bed, recycled glass aggregate manufactured to a uniform, sharp-free specification has been demonstrated in other countries. With technical input from the RMC, we were interested in bringing it to Pennsylvania."

Originally developed by the Max-Planck Institute of West Germany and the Netherlands approximately 30 years ago, the recycled glass process has been approved by the U.S. Department of Environmental Protection and has been used in on-lot sand mound septic systems for about a decade. NLCA is currently using 800 tons of processed, crushed, size-graded and color-mixed container glass obtained from Cougle's Recycling of Hamburg, PA, an amount roughly equivalent to what a rural Pennsylvania county may collect in 2.5 years. "No one has put this into an application of this size," adds Coyle.

The NLCA wastewater treatment plant was constructed in 1979 and upgraded in 2013 in compliance with the Chesapeake Bay Tributary Strategy. To comply with the Chesapeake Bay Tributary Strategy, the plant diverts significantly more solids to the reed beds than in previous years. This, along with competitive pricing for the sharp-free, recycled glass aggregate, made the decision to use it realistic.

"Proper processing of solids is a major issue faced by wastewater treatment plants such as NLCA's plant, especially those who require compliance with the Chesapeake Bay Tributary Strategy" says Robert Bylone, PRMC president and executive director. "They've taken an existing treatment method and built on its sustainability by using a recycled-content product. For these reasons, and for the courage of the Northern Lancaster County Authority to pioneer recycled glass aggregate for this use, we are proud to recognize them with the William M. Heenan, Jr. Recycling Markets Development Award."

The 2016 Reed Bed Upgrade was a win-win for all parties involved. Fred Ebert, president, Ebert Engineering, NLCA's consulting engineer; Jason Coyle, NLCA superintendent; Scott Davis, president, Constructed Wetlands Group; and Wayne Bowen, recycling program manager, PRMC, combined technical knowledge and research to bring the successful project together. Using Cougle's Recycling's manufactured recycled glass aggregate saved thousands of dollars of freight expense compared to hauling the nearest available sand from Delaware or Maryland. Donald Kellenberger, of Kellenberger Excavating in Spring Township, said final grading of the recycled glass aggregate was easier than sand. Don observed that the manufactured recycled glass aggregate held its shape and position better than the sand. This ease of installation resulted in significantly less time to complete installation, reducing total install time to less than two (2) weeks.

The Northern Lancaster County Authority was the first reed bed biosolids treatment system in Pennsylvania. With over 80 reed bed systems treating biosolids in Pennsylvania, the authority has opened a door for using recycled glass both here and across the nation. "PRMC will continue to expand this use across Pennsylvania and potentially the nation," adds Bylone. "A win for the environment while simultaneously reducing construction costs for the residents of Brecknock Township and excelling treatment output made receiving the 2016 Heenan Award very rewarding," says Jason Coyle.

The William M. Heenan, Jr. Recycling Markets Development Award is the only award if its type given annually in Pennsylvania and is named in memory of William M. "Bill" Heenan, Jr. Heenan was a lifelong international ambassador of the recycling industry who was instrumental in supporting the Pennsylvania Department of Environmental Protection to initially vision and fund inception of the PRMC.

Organized as a non-profit corporation, PRMC develops and expands the use of recycled materials and recycled content product markets in Pennsylvania. PRMC is the keystone of economic development through recycling and to manufacturing resources for support of recycled content product development. With refined expertise in assistance for markets development, materials use, applied research, business assistance, and technical training, PRMC is headquartered at Penn State Harrisburg with satellite offices near Pittsburgh and Philadelphia. The center is funded in part by the Pennsylvania Department of Environmental Protection. For more information, visit www.pennrmc.org.